The invention relates to an electro-mechanical pivot wing drive for pivoting wings of doors or the like.
An electro-mechanical pivot wing drive for pivoting wings of doors or the like is known, for example, from German Patent Publication DE 32 02 930 C2 and comprises an electric motor with a planetary gear disposed in an axial direction in respect to the shaft of the electric motor, which is fixedly connected with the housing of the electric motor. This is followed by a bevel wheel gear drive with two oppositely located free ends of a power take-off shaft. Because of this it is possible to employ the entire component for controlling a left or a right door wing without further pole-reversal steps. For this purpose the entire arrangement is embodied in the housing symmetrically to the center longitudinal plane, the shaft of the electric motor or the longitudinal shaft of the planetary gear which is identical with it extend through the shaft of the power take-off shaft approximately in its center.
In case of a power failure it is intended to provide a restoring spring unit, preferably in the form of a helical spring, as a further safety measure, which is always seated on the end of the drive shaft opposite to a linkage of bars needed for opening and closing the wing and which is supported on the one side on the drive shaft and on the other at the housing.
Two cam disks, via which the electric voltage for the electric motor can be charged with a voltage which is opposite to the respective movement direction, are provided to make possible a certain amount of optimization during the closing and opening operations. By these means, braking of the door prior to attaining the extreme opened or closed position is obtained. Otherwise the electric motor can be charged with a high voltage for accelerating the wing out of its end position (closed or open position) in accordance with the polarity, and during pivoting of the wing into the other end position with a lesser voltage.
However, the known electro-mechanical drive has the disadvantage that on the one hand the planned helical spring would have to be made sufficiently strong to be able to perform the closing movement in an adequate amount of time. On the other hand, however, because of this the door is slammed shut suddenly at a high speed, which is not only surprising and completely unusual, but possibly even dangerous. It is particularly disadvantageous that the closing movement of the door during the closing operation itself is performed with a greatly changing force. The closing kinematics are therefore very varied compared with customary known hydraulic door closers which can close a door evenly to a great extent, as is known.
Finally, the entire motor control has disadvantages because in this case an adaptation to specific requirements is not possible.
British Patent Publication GB-A-2,206,926 also discloses a pivot wing drive having a large-dimensioned helical screw preferably disposed co-eccentrically to a rotor/stator arrangement. The one end of the helical spring is supported fixed on the housing, while the opposite end of the helical spring is connected with the power take-off shaft of the drive unit which is coupled with the pivot wing door. Opening of the door takes place against the force of this helical spring. It is intended by means of the known drive to recover in the closing phase the energy of the spring element, which exceeds the restoring force of the spring element required for the desired closing movement of the door, along with simultaneous braking of the closing movement of the door in the main phase of the closing movement. When the door is only slightly open, preferably less than 5.degree., the final closing of the door is accomplished by using the recovered energy in order to assure closing of the door. For this purpose the pivot wing drive is provided with a rotor, a stator and an energy storage device, wherein the electric motor is used and operates selectively as a generator or an electric motor, depending on the requirements. It can be seen from the specification and in particular from FIG. 1 of this pre-published document, that the moment of torque shown in FIG. 1 and acting on the door is more than six times stronger at the time of the maximal opening position of the door than at the start of the opening path of the door. However, this results in that particularly at the start of the closing movement the door is moved into the closed position, and that the closing movement of the door itself in the course of the closing operation is performed with greatly changing force. This not only requires different closing kinematics but also, in case of a power failure, opening kinematics which are completely different in respect to conventional hydraulic door closers, because the opening forces required during opening of the pivot wing change greatly over the entire opening range, i.e. increase enormously.
In a door opening mechanism known from US Patent Publication U.S. Pat. No. 3,237,932, the drive shaft of the electric motor also extends in the long direction of the housing. The gear transmission from the coupling output shaft to the shaft is accomplished comparatively elaborately by the use of an arrangement of a ball-spindle and a toothed rack. A restoring spring device is installed in the housing in the axial direction, lying laterally near the drive transmission members including the toothed rack and the other toothed wheels, namely being axially offset in the axial direction in respect to the electric motor. In this case the restoring spring is of a comparatively small size.
During closing of the door the generator is short-circuited for generating a magnetic counter-force for creating a braking effect to affect the closing speed of the door.
However, this embodiment also causes a large change in the opening forces required for opening a pivot wing door, i.e. they increase greatly.